[Update on the zoonotic potential of Chlamydia]. / Update zum Zoonosepotential von Chlamydien.

INTRODUCTION: Knowledge of the obligate intracellular bacteria from the Chlamydiaceae family has increased significantly in recent years. Not only new chlamydia species, such as Chlamydia avium or C. buteonis in birds have been described, but also known chlamydia in new host species, such as C. psittaci in horses. This review article provides an up-to-date overview of the zoonotic potential of C. psittaci, C. abortus, C. caviae and C. felis and summarizes current findings on other chlamydia species in different animal species; supplemented by information on optimal sampling and pathogen detection.

INTRODUCTION: Les connaissances sur les bactéries intracellulaires obligatoires de la famille des Chlamydiaceae ont considérablement augmenté ces dernières années. Non seulement de nouvelles espèces de Chlamydies, telles que Chlamydia avium ou C. buteonis chez les oiseaux, ont été décrites, mais également des Chlamydies déjà connues ont été mises en évidence chez de nouvelles espèces hôtes, telles que C. psittaci chez les chevaux. Cet article de synthèse fournit une vue d'ensemble actualisée du potentiel zoonotique de C. psittaci, C. abortus, C. caviae et C. felis et résume les connaissances actuelles sur d'autres espèces de Chlamydies chez différentes espèces animales ; il est complété par des informations sur l'échantillonnage optimal et la détection des agents pathogènes.

Inconspicuous post-mortem findings in rabbits from Switzerland naturally -infected with Rabbit Haemorrhagic -Disease Virus 2.

INTRODUCTION: Rabbit Haemorrhagic Disease Virus 2 (RHDV-2) emerged in France in 2010. In Switzerland, RHDV-2 was first identified in 2015 and apparently has almost replaced the classical Rabbit Haemorrhagic Disease Virus (RHDV) by now. Like RHDV, RHDV-2 causes a viral hepatitis with a peracute course and an increased mortality rate within the rabbitry. RHDV infection causes consistent gross pathological findings, especially in the liver and respiratory tract. Reports about gross pathology for animals naturally infected with RHDV-2 is scarce. The present study analysed the anamnesis and necropsy reports of 35 rabbits examined during routine diagnostics between March 2015 and May 2017. A reverse transcriptase real-time polymerase chain reaction (RT-qPCR) specific for RHDV-2 and RHDV proved a total of 25 animals to be positive for RHDV-2, while none was positive for RHDV. Additionally, histological examinations were performed on liver, lung, and kidney of 18 rabbits that had tested positive by RHDV-2 RT-qPCR. The anamnestic report more often stated an increased mortality rate in RHDV-2 positive (16/18, 89 %) compared to RHDV-2 negative rabbits (3/9, 33 %). Gross pathology did not reveal any pathognomonic changes in RHDV-2 positive animals. Histologically, the liver showed the most severe lesions followed by lung and kidney. Animals positive for RHDV-2 frequently showed signs of gastro-intestinal disease (n = 5) and/or septicaemia (n = 6) masking possible indicators of an RHDV-2 infection, such as the rather unspecific findings of an enlarged spleen or an enlarged, friable, tan-coloured liver. The authors want to raise awareness among clinicians and pathologists that in case of sudden death in commercial or pet rabbits, RHDV-2 needs to be considered as differential diagnosis and should be confirmed by laboratory diagnosis.

INTRODUCTION: Le virus 2 de la maladie hémorragique du lapin (RHDV-2) est apparu en France en 2010. En Suisse, le RHDV-2 a été identifié pour la première fois en 2015 et semble avoir presque remplacé le virus classique de la maladie hémorragique du lapin (RHDV). Comme le RHDV, le RHDV-2 provoque une hépatite virale avec une évolution suraiguë et un taux de mortalité élevé chez les lapins. L'infection par le RHDV entraîne des constatations pathologiques bruts cohérents, notamment au niveau du foie et des voies respiratoires. Les rapports sur la pathologie macroscopique des animaux naturellement infectés par le RHDV-2 sont rares. La présente étude a analysé les rapports d'anamnèse et de nécropsie de 35 lapins examinés lors de diagnostics de routine entre mars 2015 et mai 2017. Une réaction en chaîne par polymérase en temps réel à la transcriptase inverse (RT-qPCR) spécifique pour le RHDV-2 et le RHDV a prouvé qu'un total de 25 animaux étaient positifs pour le RHDV-2, tandis qu'aucun n'était positif pour le RHDV. De plus, des examens histologiques ont été réalisés sur le foie, les poumons et les reins de 18 lapins qui avaient été testés positifs par RT-qPCR pour le RHDV-2. Le rapport anamnestique faisait plus souvent état d'un taux de mortalité accru chez les lapins RHDV-2 positifs (16/18, 89 %) que chez les lapins RHDV-2 négatifs (3/9, 33 %). La pathologie macroscopique n'a révélé aucun changement pathognomonique chez les animaux RHDV-2 positifs. Sur le plan histologique, le foie présentait les lésions les plus graves, suivi des poumons et des reins. Les animaux positifs pour le RHDV-2 présentaient fréquemment des signes de maladie gastro-intestinale (n = 5) et/ou de septicémie (n = 6) masquant les indicateurs possibles d'une infection par le RHDV-2, tels que les découvertes plutôt peu spécifiques d'une rate hypertrophiée ou d'un foie hypertrophié, friable et de couleur beige. Les auteurs souhaitent sensibiliser les cliniciens et les pathologistes au fait qu'en cas de mort subite chez des lapins d'élevage ou de compagnie, le RHDV-2 doit être considéré comme un diagnostic différentiel et doit être confirmé par un diagnostic de laboratoire.

[Health, performance and use of medication in professional Swiss meat rabbit production]. / Gesundheit, Leistung und Medikamenten­einsatz in der professionellen Schweizer Fleischkaninchenproduktion.

INTRODUCTION: Husbandry conditions for rabbits in Switzerland are at a high animal welfare level in international comparison. Wire mesh flooring is prohibited and group housing is mandatory up to the age of eight weeks. Despite these animal-friendly husbandry standards, animal losses seem to be a significant problem, although reliable data on professional Swiss meat rabbit production is lacking to date. A herd survey was carried out in 52 rabbit farms to address this situation. At the same time, each new litter and each fattening group was documented with a standardized form focusing on animal death and the use of medication by the farmer over a one year period. In the case of increased mortality or new health problems, dead rabbits were sent to the National Reference Center for Poultry and Rabbit Diseases (Zurich) for pathological examination including bacteriological and parasitological diagnostics. Data from 32 farms were evaluated. The average mortality of young animals (birth to weaning) was 14.9% (1.0-30.0%) and of fattening rabbits (weaning to slaughter) 17.3% (4.3-31.8%). Intestinal diseases, mainly dysentery, intestinal coccidiosis and mucoid enteropathies, were the primary cause of death (68.2%). Eimeria spp., Escherichia coli and Clostridium perfringens were identified as the most frequent pathogens. Respiratory diseases were found in 18.7% of the examined rabbits, with Pasteurella multocida identified as the most common pathogen. 60.0% of the farms used antibiotics during the study period and a third (34.7%) of all the fattening animals were medicated with at least one antibiotic. The present results confirm that despite high animal welfare standards infectious diseases and mortality rates represent a considerable problem in professional Swiss meat rabbit production. Risk factors of increased morbidity and mortality should be identified to improve rabbit health, to reduce the high mortality rate and the extensive use of antibiotics in professional Swiss meat rabbit production. Practicable management improvements with specific prevention strategies should be developed.

INTRODUCTION: Les conditions d'élevage des lapins en Suisse sont d'un niveau élevé en comparaison internationale. Il est interdit de les garder sur un sol en treillis métallique et leur détention en groupe est obligatoire jusqu'à l'âge de huit semaines. Malgré ces normes d'élevage respectueuses des animaux, les pertes d'animaux semblent être un problème important, les données fiables sur la production professionnelle suisse de lapins de boucherie faisant largement défaut à ce jour. Afin de remédier à cette situation, une enquête d'exploitation a été réalisée dans 52 élevages cunicoles. En parallèle, chaque nouvelle portée et chaque groupe d'engraissement était documenté par le chef d'élevage avec un formulaire standardisé au cours d'une année, l'accent étant principalement mis sur les pertes d'animaux et l'utilisation de médicaments. En cas d'augmentation de la mortalité ou de nouveaux problèmes de santé, les lapins morts étaient envoyés au Centre national de référence pour les maladies de la volaille et des lapins (Zurich) pour une autopsie comprenant des examens bactériologiques et parasitologiques. Les données de 32 entreprises ont pu être évaluées. La mortalité moyenne des jeunes animaux (de la naissance au sevrage) était de 14,9% (1,0­30,0%), celle des lapins à l'engrais (du sevrage à l'abattage) était de 17,3% (4,3­ 31,8%). Les maladies intestinales ont été retrouvées en premier lieu (68,2%), principalement la dysenterie, suivie par la coccidiose intestinale et les entéropathies mucoïdes. Eimeria spp., Escherichia coli et Clostridium perfringens ont été identifiés comme les agents pathogènes les plus fréquents par ordre décroissant. Des maladies respiratoires ont été trouvées chez 18,7% des lapins examinés, le pathogène le plus courant étant Pasteurella multocida. 60,0% des élevages examinés ont utilisé des antibiotiques au cours de la période d'étude, environ un tiers (34,7%) de tous les processus d'engraissement examinés ont été traités avec au moins un antibiotique. Les résultats confirment que les maladies infectieuses et les pertes de lapins en Suisse représentent un problème considérable dans l'élevage professionnel malgré un élevage respectueux des animaux. Afin d'améliorer la santé des lapins dans les entreprises de production professionnelles suisses et de réduire ainsi les taux de mortalité élevés et l'utilisation intensive d'antibiotiques, les facteurs de risque d'augmentation de la morbidité et de la mortalité doivent être déterminés dans une étape supplémentaire afin de développer des améliorations de gestion réalisables dans le cadre de stratégies de prévention spécifiques.

From fragmented levels of care to integrated health care: Framework toward improved maternal and newborn health.

Worldwide, health systems and care approaches vary widely due to local reality, distance to facilities, cultural norms, resources, staff availability, geography, and politics. Consequently, globally maternal-newborn dyad care and outcomes are highly variable, leading to approximately 800 maternal deaths daily with a 100-fold difference among high- and low-resource countries. Irrespective of where care is received, maternal safety and wellbeing should be preserved. Despite ongoing efforts, however, this is not the case. Large gaps exist between spending and clinical outcomes. Segmented health care, coupled with poor planning and inadequate resource distribution, results in failure to provide essential life-saving treatment. The proposed solution is a regional integrated care model from midwife to advanced level III/IV care and the newborn unit, achieved through effective coordination by site, staff, and clinicians. This model has been successfully implemented in high- to low-resource countries in the past 20 years. In the large diverse population of the United States, constructive steps have been implemented to reduce high maternal mortality in black and rural communities. The COVID-19 pandemic demonstrates the feasibility of rapid resources coordination to provide effective advanced care. The proposed integration of resources will have a major positive impact on the maternal-newborn dyad.

The MRN complex is transcriptionally regulated by MYCN during neural cell proliferation to control replication stress.

The MRE11/RAD50/NBS1 (MRN) complex is a major sensor of DNA double strand breaks, whose role in controlling faithful DNA replication and preventing replication stress is also emerging. Inactivation of the MRN complex invariably leads to developmental and/or degenerative neuronal defects, the pathogenesis of which still remains poorly understood. In particular, NBS1 gene mutations are associated with microcephaly and strongly impaired cerebellar development, both in humans and in the mouse model. These phenotypes strikingly overlap those induced by inactivation of MYCN, an essential promoter of the expansion of neuronal stem and progenitor cells, suggesting that MYCN and the MRN complex might be connected on a unique pathway essential for the safe expansion of neuronal cells. Here, we show that MYCN transcriptionally controls the expression of each component of the MRN complex. By genetic and pharmacological inhibition of the MRN complex in a MYCN overexpression model and in the more physiological context of the Hedgehog-dependent expansion of primary cerebellar granule progenitor cells, we also show that the MRN complex is required for MYCN-dependent proliferation. Indeed, its inhibition resulted in DNA damage, activation of a DNA damage response, and cell death in a MYCN- and replication-dependent manner. Our data indicate the MRN complex is essential to restrain MYCN-induced replication stress during neural cell proliferation and support the hypothesis that replication-born DNA damage is responsible for the neuronal defects associated with MRN dysfunctions.

Bovine respiratory disease: efficacy of different prophylactic treatments in veal calves and antimicrobial resistance of isolated Pasteurellaceae.

The present study was conducted to evaluate the efficacy of two prophylactic antibiotic treatments against bovine respiratory disease (BRD) in veal calves. In addition, the antibiotic susceptibilities of isolated Pasteurellaceae were tested. The calves were treated either on the day of arrival by a single administration of tulathromycin (group A, n=20), by a peroral administration of chlortetracycline, sulphadimidine, and tylosin (group B, n=20) for seven consecutive days, or were not prophylactically treated (group C, n=19). On the first day of clinically diagnosed BRD, transtracheal lavage samples were obtained prior to therapeutic treatment and were subsequently cultured. Pasteurellaceae isolates were tested for their susceptibility to 12 antimicrobial agents by the determination of the minimal inhibitory concentrations. During the first 56 d after arrival, different calves in group A and B suffered from one episode of clinically diagnosed BRD while calves of group C experienced two episodes. The average daily weight gain during the same period was significantly lower in group C (0.89 ± 0.04kg/d) than in the two prophylactically treated groups (1.14 ± 0.05 and 1.15 ± 0.04 kg/d for group A and B, respectively). The improved performance of groups A and B in comparison to group C could be related to a lower incidence of respiratory disorders during the first days after arrival in the prophylactically treated animals. No differences in the clinical efficacy were seen between the two tested prophylactic treatments. The most prevalent bacterial pathogens isolated (n=79) were Pasteurella multocida (23% of isolated pathogens), Mycoplasma bovis (18%), and Mannheimia varigena (16%). For the isolated Pasteurellaceae, a high resistance pattern was observed to tylosin (83% of the tested P. multocida and 88% of the Mannheimia spp. isolates resistant) and tilmicosin (56% of the tested P. multocida isolates non-sensitive).

Septicaemia caused by Edwardsiella tarda and Plesiomonas shigelloides in captive penguin chicks.

Three cases of fatal septicaemia due to Plesiomonas shigelloides and one due to Edwardsiella tarda were diagnosed in newborn penguins from the Basle Zoo, Switzerland from 2003 to 2007. The affected penguins were of two different species (king penguin, Aptenodytes patagonicus, and African penguin, Spheniscus demersus) and between 2 and 10 days old at the time of death. The causative agents, E. tarda and P. shigelloides are ubiquitous bacteria which are reported to be present in the normal intestinal flora of wild and captive aquatic animals, including penguins. Their occurrence and infectious potential is discussed.

[Swine dysentery eradication in a grower-finisher farm in Switzerland]. / Die Sanierung der Schweinedysenterie in einem Schweizer Aufzucht-Mastbetrieb.

On a Swiss grower-finisher farm blood-tinged-diarrhoea in pigs weighing 40 to 60 kg was observed during several months, resulting in reduced feed efficiency and a prolonged fattening period. As part of a research project, in February 2007 faecal samples were analysed and one diseased pig was euthanised and sent for necropsy where typical gut lesions indicative for a Brachyspira (B.) hyodysenteriae infection were found. B. hyodysenteriae was demonstrated by PCR in 4 out of 5 faecal samples. The pig farm thereafter underwent an eradication process with timed depopulation of the consecutive pigpens. During February to June 2008 the farm was regularly inspected and tested for B. hyodysenterieae. Testing continued for another year after the eradication process and all faecal samples proved negative. Until January 2010 neither diarrhoea with blood nor B. hyodysenterieae reoccurred.

[Mucormycosis due to Mycocladus corymbiferus in a fattening pig]. / Mucormykose durch Mycocladus corymbiferus bei einem Mastschwein.

A fattening pig with enlarged head and abdominal lymph nodes was examined. An aspirate of the abscesses did not produce a conclusive diagnosis. Only an excision with subsequent histological and bacteriological examination showed the mould Mycocladus corymbiferus (syn. Absidia corymbifera) to be present. Similar abscesses should be examined as actinomycosis and leucosis are the main differential diagnoses.

Cross-sectional study of Streptococcus species in quarter milk samples of dairy cows in the canton of Bern, Switzerland.

A total of 2538 quarter milk samples from 638 lactating dairy cows from 47 farms in the canton of Bern, Switzerland, were investigated for streptococci. A novel, simple and inexpensive laboratory method was used for the differentiation of Streptococcus species, and a risk factor analysis was carried out. The prevalence in the quarter milk samples was 0.2 per cent for Streptococcus agalactiae, 1.3 per cent for Streptococcus uberis, 1.3 per cent for Streptococcus dysgalactiae, 0.1 per cent for Enterococcus species and 2.9 per cent for minor Streptococcus species (designated Streptococcus-Lactococcus-Enterococcus [SLE] group). Based on the somatic cell count (SCC), S uberis and S dysgalactiae were classified as 'major' pathogens and the bacteria in the SLE group as 'minor' pathogens. For S uberis, S dysgalactiae and bacteria in the SLE group, the most significant risk factor was an intramammary infection (IMI) of a neighbouring quarter by the same pathogen. Other significant risk factors for S uberis infection were a positive California Mastitis Test (CMT) result and a SCC of more than 100,000 cells/ml. Significant risk factors for IMI with S dysgalactiae were a positive CMT result, teat injury and palpable abnormalities in the udder. Infection with bacteria in the SLE group was significantly associated with a SCC of more than 100,000 cells/ml, a lactation number of more than 2, the right rear quarter (as the location of infection) and a positive CMT result.

Retrospective study on necrotizing enteritis in piglets in Switzerland.

The re-emergence of necrotizing enteritis (NE) in Swiss pig breeding farms raised concern that, besides C. perfringens type C strains, additional C. perfringens toxinotypes might cause this disease. Therefore we retrospectively investigated the association of NE with C. perfringens type C or different C. perfringens toxinotypes. We evaluated pathological lesions, routine diagnostic bacteriology results, and multiplex real-time PCR analyses from DNA extracts of archived intestinal samples of 199 piglets from our diagnostic case load. 96.5% of NE cases and 100% of herds affected by NE were positive for C. perfringens type C genotypes. Animals without necrotizing enteritis revealed a significantly lower detection rate of type C genotypes. Non affected piglets showed a high prevalence for beta-2-toxin positive C. perfringens type A strains. Collectively, our data indicate that outbreaks of NE in piglets in Switzerland cannot be attributed to newly emerging pathogenic toxinotypes, but are due to a spread of pathogenic C. perfringens type C strains.

[Occurrence of Clostridium perfringens type A and type C in piglets of the Swiss swine population]. / Vorkommen von Clostridium perfringens Typ A und Typ C bei Saugferkeln in der schweizerischen Schweinepopulation.

Necrotizing enteritis (NE) of newborn piglets still represents an economical problem in Swiss pig breeding and production. The aim of our study was to identify risk factors for NE and evaluate the prevalence of C. perfringens with the toxingenes cpb and cpb2 in Swiss pig breeding farms. The prevalence of theses C. perfringens was investigated using fecal swabs followed by bacteriological culturing and genotyping. Close proximity to other breeding farms and large herd sizes were shown to predispose to NE. C. perfringens type C, carrying the genes cpa, cpb and cpb2 were frequently identified in herds with acute outbreaks of NE. Farms not affected by NE or those using prophylactic vaccination against NE were predominantly positive for C. perfringens type A strains with cpb2 and showed much lower prevalence of C. perfringens type C, compared to acutely affected herds. Our results demonstrate that C. perfringens type A strains with cpb2 are not associated with NE. Besides typical necropsy finding, only the identification of cpb can be used for the diagnosis of NE in affected herds.

Stenotrophomonas maltophilia isolated from the airways of animals with chronic respiratory disease.

Stenotrophomonas maltophilia (S. maltophilia) is a nonfermentative bacterium, which is naturally resistant against a panel of commonly-used antibiotics. It is frequently isolated from humans with chronic respiratory disease, e.g. cystic fibrosis or chronic obstructive pulmonary disease. In veterinary medicine S. maltophilia is perceived to be a mere coloniser. We herewith report 7 strains of S. maltophilia isolated from animals, of which 5 strains were harvested from 3 horses, a dog and a cat with chronic respiratory disease. The dog isolate showed resistance to trimethoprim / sulphamethoxazole, which was confirmed by detection of the sul 1 gene. Analysis with pulsed field gel electrophoresis revealed that 2 horses, which were boarded in the same clinic but two years apart, harboured the same strain of S. maltophilia. This is indicative of a hospital acquired colonisation / infection, which contradicts involvement in the pre-existing chronic disease.

Prevalence study of Staphylococcus aureus in quarter milk samples of dairy cows in the Canton of Bern, Switzerland.

In the present study, the prevalence of S. aureus in mammary gland quarters of dairy cows in Switzerland was estimated and a risk factor analysis was carried out. Dairy cows were selected by one-step-cluster sampling with stratification by herd size. Forty-seven of 50 randomly chosen farms participated in the study, resulting in 603 cows and 2388 quarter samples. Milk samples were collected in all herds on two occasions two weeks apart. In 6% of cows (95% CI: 2.7-9.3%) at least one milk sample was positive for S. aureus and from 2% (0.8-3.2%) of all quarters, S. aureus was cultured at least once. In four quarters a latent S. aureus infection (agent detected and somatic cell count (SCC) <100,000cell/ml) was diagnosed. Multivariable hierarchic logistical regression analysis yielded five significant risk factors for observing S. aureus in a milk sample: high SCC, a S. aureus-positive neighbouring quarter, a palpable induration in the quarter, and a wound, scar tissue or crush injury affecting the teat. The type of housing (P=0.1596) was also a factor that remained in the model. The mentioned risk factors must be considered during the evaluation of herds with S. aureus problems. The occurrence of latent S. aureus infections emphasises that not only quarters with a high SCC but all quarters of all cows must be cultured for control measures to be effective.

Prevalence of four enteropathogens in the faeces of young diarrhoeic dairy calves in Switzerland.

The prevalences of Cryptosporidium parvum, rotavirus, bovine coronavirus (BCV), and enterotoxigenic Escherichia coli (E coli K99) were determined in diarrhoeic dairy calves aged one to 21 days on 71 dairy farms in western Switzerland during the winter of 2005 to 2006. Faecal samples from 147 untreated calves suffering from acute diarrhoea were analysed by standardised diagnostic methods, and the immunoglobulin status of each calf was evaluated. The prevalences of C parvum, rotavirus, BCV and E coli k99 were 55.0 per cent, 58.7 per cent, 7.8 per cent and 5.5 per cent, respectively. The proportions of herds positive for the respective pathogens among the herds with diarrhoeic calves were 41.7 per cent, 52.1 per cent, 2.1 per cent and 2.1 per cent. The immunoglobulin concentration in the serum of 90.5 per cent of the diarrhoeic calves was below 8 g/l.

Real-time multiplex PCR assays for reliable detection of Clostridium perfringens toxin genes in animal isolates.

Typing of Clostridium perfringens strains by PCR-based determination of toxin genes proved to be a reliable method for diagnosis of enterotoxaemia in various animal species. We report the establishment and validation of three real-time fluorogenic (TaqMan) multiplex PCRs for the detection of C. perfringens alpha-, beta-, beta2-, epsilon-, entero- and iota-toxin genes. The composition of the PCRs was chosen with regard to robustness of the assays and in order to increase sensitivity compared to the conventional simplex PCRs. The combination of probe dyes selected for the real-time assays (FAM/TAMRA, Cy-5/BHQ-2 and VIC/TAMRA) as well as the designation of the chromosome-borne alpha-toxin as internal positive control allowed the creation of highly specific and sensitive, as well as time and cost effective PCRs. One hundred and three strains of C. perfringens isolated in Switzerland derived from clinical or suspected cases of enterotoxaemia in 10 different animal species were tested. The toxin genotypes were in agreement in both the conventional PCRs and the newly designed multiplex PCRs. Furthermore, the real-time PCR carried out as simplex allows to quantitate the copy numbers of plasmid-borne toxin genes in relation to the chromosomally located alpha-toxin gene.